What is the Alternative Investment Market (AIM)?

■ AIM is a sub-category of the London Stock Exchange which allows smaller companies to float shares with a more flexible regulatory system than the main market.

■ It launched on June 19, 1995, and has raised almost £24 billion , helping more than 3,000 small-medium-sized companies.

■ Companies from high-growth areas such as technology and biotech are listed on AIM.

■ Though some companies move to the main market from AIM – in recent years more have moved in the opposite direction, due to the tax advantages and the regulatory system.

■ As of February this year, the top company listed on AIM was internet retailer ASOS, with a market capitalisation of more than £5.8billion.

But for the 46-year-old, who grew up in Jenny Path in Harold Hill, it became a reality yesterday (Thu) when his genetics-based life science company, Horizon Discovery, began trading on the Alternative Investment Market (AIM).

The company uses its trademark Genesis “toolbox” to develop more than 550 patient-relevant disease models, identifying mutations found in patients with cancer and other diseases.

This helps researchers understand how complex diseases manifest themselves, and how patients react to certain treatment.

It is sold as X-Man, the companies flagship product that Darrin refers to as “patients in a test tube.”

Darrin Disley (front row, third right) was goalkeeper for the successful Bedfords Park school football team. A number of the players went on to become professional footballers

“Take cancer - a genetic-based disease,” he explained.

“What we have in the genome [genetic material] will predispose whether we get it and how we will respond to drugs. Chemotherapy and radiotherapy just kill us slower than the cancer. This makes sure patients get the right drugs and not the one-size-fits-all drugs.”

Formed in 2005, the company now sells to 45 countries around the world and has gone from being worth £10,000 in March 2008, to $200m [£120.5m] as of this week.

The company is based in Cambridge, but the life Darrin now leads is a long way away from his life as a schoolboy at Bedfords Park Comprehensive.

Horizon Discovery: How does it work?

“I spent most of my time playing football,” said Darrin, goalkeeper in the highly successful school team.

“We had a great team. Steve Mackenzie who scored for Manchester City in the 1981 FA Cup final went to the school, I remember when they signed him in assembly!”

Darrin himself played semi-professionally for local teams including Dagenham and Redbridge, and Hornchurch, but upon his return from coaching in the United States he decided to look elsewhere for a career.

“I became interested in science when I was 13,” said Darrin. “I worked as a lab technician and then went to the University of Salford where I studied chemistry.

“Then came biochemistry, which was brand new at the time. I went to Cambridge where I got my PhD.”

It was there he worked for Christopher Lowe, who in 2006 was named the most entrepreneurial scientist in the UK.

Darrin said: “I went on to set up a lot of companies. My first was a consulting company called Xanax, which of course in America is a mental illness drug.

“I learnt a lot through that though, like how to focus on the customers and not yourself. Then Horizon came along, which has been a spectacular success.”

Darrin’s humble beginnings have ensured he always has one eye on the youth of today, and as well as teaching entrepreneurship at Cambridge, he has set up a charity helping poorer students study at Oxbridge.

He said: “It’s a big passion of mine. Growing up where I did there was a lot of talented people who didn’t get the opportunities - I am looking to provide opportunities.”

Darrin’s sister still lives in Harold Hill, while his mother has “remained independent for as long as possible” and lives in Harold Wood.

“She’s very proud,” said Darrin. “She doesn’t understand everything I do 100 per cent - but she’s looking forward to seeing me in the Romford Recorder!”

His success story has not finished yet though, and as his Horizon embarks on a new chapter, Darrin is looking to increase the products, services and visibility.

He added: “Our aim now is to use the cash, not to sit on it. We are looking at acquiring companies in England and North America.”

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